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Updated: Aug 14, 2026
Multiplexed Immunofluorescence Analysis and Quantification of Intratumoral PD-1+ Tim-3+ CD8+ T Cells
Published on: February 8, 2018
Increased PD-1+ and TIM-3+ TILs during Cetuximab Therapy Inversely Correlate with Response in Head and Neck Cancer
Hyun-Bae Jie1, Raghvendra M Srivastava1, Athanassios Argiris2
1Department of Otolaryngology, University of Pittsburgh, Pittsburgh, Pennsylvania.
Abstract:
Despite emerging appreciation for the important role of immune checkpoint receptors in regulating the effector functions of T cells, it is unknown whether their expression is involved in determining the clinical outcome in response to cetuximab therapy. We examined the expression patterns of immune checkpoint receptors (including PD-1, CTLA-4, and TIM-3) and cytolytic molecules (including granzyme B and perforin) of CD8+ tumor-infiltrating lymphocytes (TIL) and compared them with those of peripheral blood T lymphocytes (PBL) in patients with head and neck cancer (HNSCC) during cetuximab therapy. The frequency of PD-1 and TIM-3 expression was significantly increased in CD8+ TILs compared with CD8+ PBLs (P = 0.008 and P = 0.02, respectively). This increased CD8+ TIL population coexpressed granzyme B/perforin and PD-1/TIM-3, which suggests a regulatory role for these immune checkpoint receptors in cetuximab-promoting cytolytic activities of CD8+ TILs. Indeed, the increased frequency of PD-1+ and TIM-3+ CD8+ TILs was inversely correlated with clinical outcome of cetuximab therapy. These findings support the use of PD-1 and TIM-3 as biomarkers to reflect immune status of CD8+ T cells in the tumor microenvironment during cetuximab therapy. Blockade of these immune checkpoint receptors might enhance cetuximab-based cancer immunotherapy to reverse CD8+ TIL dysfunction, thus potentially improving clinical outcomes of HNSCC patients. Cancer Immunol Res; 5(5); 408-16. ©2017 AACR.
Insights
Increased expression of PD-1 and TIM-3 on tumor-infiltrating T cells correlates with poor outcomes in head and neck cancer patients receiving cetuximab. Targeting these immune checkpoints may improve immunotherapy effectiveness.
Area of Science:
- Immunology
- Oncology
- Cancer Research
Background:
- Immune checkpoint receptors regulate T cell effector functions.
- The role of immune checkpoint receptors in cetuximab therapy outcomes for head and neck squamous cell carcinoma (HNSCC) is not well understood.
Purpose of the Study:
- To investigate the expression patterns of immune checkpoint receptors (PD-1, CTLA-4, TIM-3) and cytolytic molecules (granzyme B, perforin) in CD8+ tumor-infiltrating lymphocytes (TIL) and peripheral blood T lymphocytes (PBL) from HNSCC patients undergoing cetuximab therapy.
- To determine the correlation between the expression of these molecules and clinical outcomes.
Main Methods:
- Flow cytometry was used to analyze the expression of PD-1, CTLA-4, TIM-3, granzyme B, and perforin on CD8+ TILs and CD8+ PBLs.
- Expression levels were compared between TILs and PBLs, and correlated with clinical outcomes in HNSCC patients treated with cetuximab.
Main Results:
- CD8+ TILs showed significantly higher frequencies of PD-1 and TIM-3 expression compared to CD8+ PBLs.
- The CD8+ TIL population coexpressed cytolytic molecules (granzyme B/perforin) with immune checkpoint receptors (PD-1/TIM-3).
- Higher frequencies of PD-1+ and TIM-3+ CD8+ TILs were inversely correlated with favorable clinical outcomes in patients receiving cetuximab therapy.
Conclusions:
- PD-1 and TIM-3 expression on CD8+ TILs may serve as biomarkers for immune status during cetuximab therapy in HNSCC.
- Blocking PD-1 and TIM-3 could potentially enhance cetuximab-based immunotherapy by reversing CD8+ TIL dysfunction and improving patient outcomes.
